It is desirous to reduce the noise generated by aircraft, for example, to lessen disruption or inconvenience, resulting from aircraft noise, caused to the public on the ground near airports. A significant amount of noise is generated by the interaction of the aircraft and the air flowing past it, which results in turbulent flows and consequently noise. It is particularly important to reduce noise created during approach of the aircraft on landing. During approach, a significant contribution to the amount of noise that the aircraft generates is made by the landing gear, which is typically deployed early for landing for safety reasons. The deployment of the landing gear increases drag and assists deceleration of the aircraft. During take-off, noise from the landing gear is a less significant factor because engine noise is generally greater and because the landing gear is generally stowed at the earliest opportunity to reduce drag and aid take-off. During normal flight, the landing gear of an aircraft is typically stowed in a landing gear bay, the bay being closed off by doors so that no part of the landing gear is subjected to the air flow.
WO01/04003 describes an aircraft landing gear and apparatus including a plurality of attachments for noise reduction purposes. The attachments are shaped and positioned on the landing gear to deflect air away from noise-inducing components of the landing gear and to permit deflection and articulation movement and also stowage of the landing gear whilst the attachments are installed thereon. Noise-inducing parts of the landing gear are however still exposed to airflow.
WO2004/089743 describes an aircraft landing gear door assembly including a landing gear bay door for closing the aperture through which the landing gear is deployed. The door is additionally moveable so that at least a portion of the door acts as a fairing to reduce the noise caused by the landing gear, when the landing gear is in its fully deployed position. The landing gear bay door thus doubles up as a noise-reducing fairing. However, the ability of the door to reduce noise may need to be compromised in view of the need of the door to function additionally as a landing gear bay door. Also, complicated deployment mechanisms may need to be employed to allow the door additionally to be moved to a fairing position and/or configured as a fairing.
The present invention seeks to mitigate the above-mentioned problems. Alternatively or additionally, the present invention seeks to provide an improved aircraft landing gear noise reduction assembly.